A conventional hopper wagon comprises a hopper wagon body with a storage chamber for storing bulk commodities, an inlet formed in the top of the body through which the bulk commodities are loaded into the storage chamber, at least one closable outlet formed in the base of the body through which the bulk commodities are discharged under the force of gravity from the storage chamber, an underframe for supporting the body, a first bogie and a second bogie coupled to the underside of the underframe and control means for controlling the operation of the hopper wagon.
To optimise the capacity of the storage chamber and discharging of the bulk commodities, it is customary for the bogies to be arranged adjacent to each headstock and for the control means of the hopper wagon to be arranged externally to the storage chamber. The control means may be arranged on the outer surface of the storage chamber, in external recesses and/or on the underframe. For example, in the conventional hopper wagon shown in FIG. 1, hopper wagon control means (1) are arranged externally to the storage chamber of the hopper wagon body (2) in a recess (3) formed at the end of a hopper wagon body between an inclined end wall of the storage chamber (4) and the underframe (5). The bogies (6) of the conventional hopper wagon are arranged adjacent the respective headstocks (7) such that the at least one closable outlet (8) is arranged centrally and discharges bulk commodities between the bogies.